A chemist is studying an unknown substance and could break the substance into its elemental components only by using chemical means. Based on this observation, how should the unknown substance be classified?
impure substance
solution
mixture
pure substance

Compare the valence electron configuration of the nobles gas elements seen here. what statement is correct?

If you add 5.00 ml of 0.100 m sodium hydroxide to 50.0 ml of acetate buffer that is 0.100 m in both acetic acid and sodium acetate, what is the ph of the resulting solution? acetic acid: ka = 1.8. x 10-5

Which statement about hf is true? it is zero for any compound in its standard state. it is positive when the bonds of the product store more energy than those of the reactants. it is negative when a compound forms from elements in their standard states. it is zero for any element that is in the liquid state.